The SMTP service must not have a uudecode alias active.

From SOLARIS 10 SPARC SECURITY TECHNICAL IMPLEMENTATION GUIDE

Associated with IA controls: ECSC-1

Associated with: CCI-001230

SV-42312r1_rule The SMTP service must not have a uudecode alias active.

Vulnerability discussion

A common configuration for older Mail Transfer Agents (MTAs) includes an alias for the decode user. All mail sent to this user is sent to the uudecode program, which automatically converts and stores files. By sending mail to decode or uudecode aliases present on some systems, a remote attacker may be able to create or overwrite files on the remote host. This could possibly be used to gain remote access.

Check content

Check the SMTP service for an active decode command. Procedure: # telnet localhost 25 decode If the command does not return a 500 error code of command unrecognized, this is a finding. If telnet is unavailable for testing, check for the existence of the decode and uudecode aliases in the sendmail aliases file. Find the active sendmail aliases file. # grep AliasFile /etc/mail/sendmail.cf (The aliases file is usually at /etc/mail/aliases) Look for decode aliases in the aliases file. # grep decode /etc/mail/aliases If there is an uncommented decode or uudecode alias in the aliases file, this is a finding.

Fix text

Comment out active decode and uudecode aliases in the aliases file. # vi /usr/mail/aliases Activate updated aliases file. # newaliases

Pro Tips

Lavender hyperlinks in small type off to the right (of CSS class id, if you view the page source) point to globally unique URIs for each document and item. Copy the link location and paste anywhere you need to talk unambiguously about these things.

You can obtain data about documents and items in other formats. Simply provide an HTTP header Accept: text/turtle or Accept: application/rdf+xml.